---
title: FileUploadHandler
source: https://github.com/remix-run/remix/blob/main/packages/form-data-parser/src/lib/form-data.ts#L60
---

# FileUploadHandler

## Summary

Transforms an uploaded file into the value stored in the parsed [`FormData`](https://developer.mozilla.org/en-US/docs/Web/API/FormData).

## Signature

```ts
interface FileUploadHandler {
  (file: FileUpload): string | void | Blob | Promise<string | void | Blob | null> | null
}

```